Correction to This Article
An earlier version of this article incorrectly said that two companies that own local power plants, Mirant and Constellation Energy, also own the mines that supply their coal. The companies buy the coal from other businesses. .

MUD, W.Va. -- This is a place where "moving mountains" is no longer a figure of speech. Here, among the steep green Appalachians, mining companies are moving mountains off their pedestals to get the kind of coal that Washington needs.

It happened here, on a ridgeline called Sugar Tree Mountain, where locals once hunted for squirrels and puckery-sour grapes. Then the top was scraped off to expose the black seams in its innards, leaving a rock-strewn plateau.

"It used to be West Virginia," said Vivian Stockman, an environmental activist. "And now it's Mars."

Though this isolated mine is more than 400 miles from Washington, the two places share a powerful connection: coal. The D.C. region, with its need for electricity skyrocketing, has been burning steadily more coal, buying almost a third of its supply from this part of Appalachia.

And that, analysts and environmentalists said, means that Washington's air conditioners and iPods have helped drive the region's "mountaintop" mining.

The coal industry and the Bush administration say the benefits of these mines, measured in jobs and energy, outweigh the damage.

But in West Virginia, where mining opponents can face back-roads intimidation, some neighbors say that Washington area residents might not know the true cost of their power.

"We have to go through a lot for them to get their electric," said Lucille Miller, who picked grapes on the vanished mountain.

The links that bind the cathedral-ceiling suburbs of Washington to the blasted-out mines of West Virginia can be traced through federal energy records. The Washington Post analyzed almost four years of data, showing where the six coal-fired power plants across the D.C. region bought their supply.

The records make one thing clear: The plants have been buying a lot more coal. Total purchases were more than 40 percent higher in 2006 than in 2004. The increase came as the Washington region's demand for electricity grew 18 percent since 2001, driven by population growth and an increasingly wired culture. D.C. area plants do not send their electricity straight to local homes but feed it into the multi-state regional power grid.

Records also show that about 32 percent of the coal the plants bought came from one kind of mine in this corner of Appalachia -- a "surface" operation, where miners do not have to tunnel.

The region, where southern West Virginia meets western Virginia and eastern Kentucky, is home to the vast majority of mountaintop mines in the United States.